Dbiving mechanism fob electbically-pro



J. KROHN. DRIVING MECHANISM FOR ELEGTRIGALLY PROPELLED VEHICLES.

APPLICATION FILED JAN. 21, 1914.

1 3,853. 4 SHEBTS-SHEET 1.

Reissue d M029, 1914.

J1 KRUHN. nmvma MEGHANZSM FOR EILECTEIGALLY PROPELLED VEHICLES AIPLIGJQTYON FILED JAN. 21, 191%.

Reissued Dec. 29, 192%.

4 SHEETS-SHEET 2.

mozm. DRIVING MECHANISM FOR ELEGTRIGA LLY PROPELLED VEHICLES.

APPLICATION FILED JAN 21, 1914.

13,853. 4 SHEETS-SHEET 3.

RGiSSllGd Dec. 29, 1914.

Reissued Dec. 29, 1914.

UNITED .rorm xaonmos cnroaco; rnunors;

nm-vma mncnnmsm r03. msc'rnicnLLY-rnornurin vamcnns.

Original No. 1,082,068, dated July 8,1812, Serial No. 578,798. Application for reissue filed January 21, 1814.

Serial No. 818,586.

To all whom it may concern Be it known that 1, JOHN Kaolin, a cit zen of the United States, residing in Chicago, county of Cook, and State of Illinois,

haveinvented certain new and useful Improvements in Driving Mechanism for Electrically-PropelledVehicles, of which the folapplications.

Among the salient objects of the invention are to provide a driving mechanism containin the fewest possible parts necessary toe ect a reduction'of the high speed Of the electric motor tothe relatively low rotative speedtof the wheels; to embody this mechanism in such small dimensions of parts and compact form as to enable the same to I tively, in cross section'through one of the be inclosed within motor housing or casing without materially' increasing the dimensions of the same; to inclose all the working arts .in a dust and dirt-proof compartment in which the gears can run in an oil bath so "dimensions of the as to reduce"wear' and tear to a minimum 'and eliminate the noise due to the outside chains and gears-as in other constructions; to provide ;a mechanism in which the gear ratio can be altered according to requirements without materially altering the caring; to provide a mechanism havingt e form and character of a complete unit which can be handled as such, and which cancompletely replace other'and more complicated mechanisms 'in existing constructions; to provide a mechanism which permitsof the car being washed without danger of flooding the driving mechanism'with water; to provide a driving, mechanism which can be manufactured- ,econ'omically, which will retain the original alinement of the parts to one another indefinitely, and which cannot be distorted in service by an uneven road surface; and to provide .a mechanism permitting the use hind. wheels, or individual motors to drive two or all of the wheels of a vehicle separately.

With' these and other minor objects in view the invention consists in the novel construction and arrangement of parts hereinafter described and more particularly point-- ed out in the claims;

Practical .forms in which my invention may be embodied are shown in the accompanying drawings, in which Figure 1 is an elevational view, partly in section, of a rear axle structure and wheels, showing my invention'as embodied in a construction employing a divided floatingaxle and a single motor driving both wheels. Fig. 2 1s an enlarged axial section through that portion of the rear:axle structure carrying the motor, drivin gear, and difi'erential orbalance gear. I ig.. 3 -is' a-vertical transverse section on the line 3'3..o- Fig. .2.

Fig. 4 is a similar cross section on? tho-line 4-4 of Fig.2. Figs. 5 and Bare fragmentary plan and felevational views, respeccation wherein an independent motor is applied to each wheel.

Referring to the drawings, 10 designates the two rear wheels of an electrically propelled vehicle, andll the hollow -bridge or gear and axle casing which, in this instance, is made sufficiently large to accommodate not only the difierential or balance gear but I Specification of Reissued Letters Patefnt. Reig gued De 29,1914. 7

also the motor and the drivingconnections between the armature shaft of the motor.

Rigidly secured j and the differential gear.

to and within the ends of the casing 11 are 'the end axle casings or tubes 12 supporting the inner stationary bearingrings13 of the usual ball-bearings '14, the outer bearing rings 15 being fast with and carried by the hubs 16 of the wheels. e

The hollow casing 11 isp'rovided with a plurality of rigid transverse webs 17, 18, 19,

and 20 (Fig. '1).-,In"and b'etwe'en the'webs 17 and 18 isrotatably mounted by ballbearings 212a hollow driving shaft 22,{Which loosely surrounds one section 23 of the divided, floating axle, the other section of said axle being shown at 24; the inner meeting ends of said axle sections are squared as shown at 23 and 24 respectively, (Fig. 2) and have mounted thereon the two main spur wheels of the dili'erential gear, as more fully hereinafter described; said axles at their outer ends extending through the stationary end axle casings 12 and being drivingly connected through spiders 25 to the hubs of the wheels, said spiders and the bearings being protected by dust-caps 26 screwed on to the outer ends of the hubs.

Fast on the hollow driving shaft 22 is the armature 27 of an electric motor, the

field whereof is indicated at 28. The shaft 22 is provided at one end with an integral eccentric head 29,. preferably made hollow for the sake of lightness; and on this eccentric head is mounted, through the agency of ,an ordinary anti-friction or ball-bearing 30,? the driving member 31 of the speed re ducing driving gear. This latter comprises the internal member 31 formed on its periphery with V-shaped teeth and the outer driven member 32 which has on its inner peripherv similar V-shaped teeth, but diiferingin number from the teeth on the member 31, the inner member having, say sixty teeth; and the outer member say sixty-four teeth; although'the ratio of the teeth may be changed with a corresponding change in the speed imparted, the speed increasing with an increase in the difi'erence in the number of teeth carried by the respective gear membars. The internal diameter of the outer member 32 is somewhat greater than the external diameter of the inner member 31, and the two are at all times in slightly eccentric relation to each other The inner gear member 31 is confined against rotation but per- 'mitted a gyratorv or circular sweeping movement within the outer gear member by means of a connection to the web 18 of such a character that itmay have a bodily radial movement in any direction; the connection herein shown comprising a disk 33 that is provided on one side with a pair of diametrically opposite radial grooves 3i and on its opposite side with a similar pair of dia metrically opposite radial grooves 35 located 90 degrees from the grooves 34; and keys 36 and 37 carried by the gear member 31 and the stationary web 18, respectively, slidably engaging said grooves.

The outer gear member 32 is rigidly secured'within and carried by an annular flange 38 formed on one end of the differential box 1' casing 39, said flange being mounted or rotary movement through an anti-friction bearing 40 in the transverse web 19 of the axle bridge. 'The outer end of the differential gear box or casing 39 is formed with a hub 4.1 which is rotatably mounted through an anti-friction bearing 42 in the transverse web 20. The difl'erential or compensating gear herein shown is the ordinary type of spur gear differential, comprising essentially the main gears 43 and 44 fast on the squared ends of the axle sections, and a plurality of pairs of spur pinions 45 and 46 rotatably mountedfon shafts 47 and 48 journa'led in the end walls of the differential casing, the pi'nions 45 meshing with the gears 43, pinions 46 meshing with the gears 44, and the two pinions being made of such length-as to overlap and mesh with each other between the main;

gears 43 and fH.

The operation will be apparent from the foregoing description of the structure of the mechanism, but-may be briefly described as the outer gear member 32, imparts a rotation, at a greatly reduced speed, to the latter, said outer gear 32, through the difi'er ential gear, transmitting this reduced speed to the axle sections. which latter transmit the rotary movement to the wheels. The type of combined driving and speed reducing gear herein shown has a number of advantages. In the first place the entire reduction of speed is effected through the use of but two gears. The gearing is economical of power, since friction between the gear teeth is practically eliminated. The V- shaped gear teeth are of simple form and easily and economically manufactured. The

speed ratio, which is approximately 1 to 16 in the structure as herein shown, can-easily he changed by substituting either an inner or -outer gear member having a difi'erent number of teeth and without requiring any change in diameter of either. r

In Fig. 8 I have shown an application of the invention wherein the wheels are driven each by an independent motor, which ar-' .rangement, of course, dispenses with the necessity of a diiferentlal gear. In this construction the stationary axle bridge 50 is formed with a compartment 51 at each end adjacent to the wheel hub, within which .is housed the field 28' and .armature 27' of the'niotor, the latter being fast on the hollow driving shaft 22. .Said drivin shaft is rotatably supported in an antiriction bearing 21 carried by the transverse web 18 of the casing, and has integral with or keyed to one end an eccentric 29' supporting, through anti-friction bearings 30', the

. out involving any essential chan stitution of an inner or the first mentioned rim,

inner gear member 31 of the driving and speed reducing gear.- The cotiperating outer "ear member 32 is rigid withand carried y a flanged disk .52, the hub53 of which latter is journaled by anti-friction bearings 54 in a transverse web 20 of the casing, said hub bein keyed on the inner end of the floating s iaft 55, this latter being drivingly connected at its outer end to the hub \of the wheel in the manner and by the means already described in connection with the form of the invention shown in hlgs. 1 to 7 inclusive.

From the foregoin it will be seen that the several objects 0% the invention specineu are attained in the mechanism described. Power is applied inore directly to the axles than has heretofore been accomplished in mechanisms of this character; the necessary reduction of speed is effected through a transmission ear ofextreme simplicity and of a practically frictionless character; the usual rear axle bridge, by a slight enlargement, is made to serve as a casing and protection not only for the differential gear employed) but for the motor and gear as (when transmission and speed reducin well; and the construction is capa ing manufactured economically, itch ratio may be varied as desired by the simple subouter gear member having a different number of teeth. It will beapparent to those skilled in the art that the details of the structure, as shown and described, may be considerably varied, within the character of'the mechanism and t e results secured thereby, and hence I do not limit the invention to the particular embodiment thereof disclosed, except to the extent clearly indicated in specific claims. I claim: r 1. In a power driven vehicle, the combination of driving axle sections each connecting at its outer end with the vehlcle drive wheel, a housing concentrically disposed about said axle sections and supported from said drive wheels, a differential transmission train within said housing surrounding the inner ends of said axle sections and connected therewith atone end, a rim at the other end of said transmission train concentric with said axle section's and having internal transmission teeth, a sleeve concentric with said axle sections and having a bearing head eccentric with said axle sections and disposed within said rim, a second rim concentrically journaled on said eccentric head and having external teeth of a different number than means for preventin axial rotation of said second rim about said head, and an electric motor having its parts mounted concentrically wzthmsaid rotation of the remaining gear, mean that of the teeth on housing about said sleeve and having its rotating element connected in driving relation with said sleeve, rotation of said sleeve and eccentric head causing radial displacement of said second rim and radial engagement of the teeth thereof with the internal teeth of the first mentioned rim whereby the axle sections are driven at a speed diii'erent from that of the sleeve axle.

2. Ina power driven vehicle, the combination of driving axle sections each connecting at its outer end with a vehicle drive wheel, a housing concentrically disposed about said axle sections and supported from said drive wheels, a difierential transmissiontrain within said housing surrounding .trio with said axle sections and having a bearing head eccentric with said axle sections and disposed within said rim a'ball bearing mounted on said eccentric bearing head, a second rim encirclin said ball bearing and having external teet of a'difierent number than that of. the teeth on the first mentioned rim, means for preventin axial rotation of said second rim about sai head, and an electric .motor having its parts mounted concentrically within said housing about said sleeve and having its rotating element connected in driving said sleeve, rotation of sai centric head causin radial displacement of said second an radial enga ement of the teeth thereof with the interna teeth of the first mentioned rim wheregy the axle sections are driven at a speed di erent from that of the sleeve axle.

3. A. driving unit for electric vehicles, comprising a vehicle supporting wheel, an internal and an external gear intermeshing one of said gears beingconnected to drive said wheel, means in its rotating element connected to operate said means.

5.'In a power driven vehicle, the combination of a vehicle supporting wheel, a pair of intermeshing internal and external gaps,

driven vehicle, the combirelation with sleeve and ecfor restraining the xflal or giv'ng said remaining gear an eccentric f 39 oi said gears having cepnections to Sigeed at Qhieage this 536th day at De dr ve said wheel, means for glving one of cember, 1913.

said gears an eccentric movement with re- JOHN KRUHN. .spect to the other gear, and an electric mo- Witnesses; 4 5 tor heaving its rotating element connected Renew RUMMLER,

to operate said means. M. IRENE Htr'xcmrme, 

